title: Annihilation upconversion in cells by embedding the dye system in polymeric nanocapsules.
abstract: The first energetically conjoined TTA-assisted photon energy upconversion operating in cell tissue is described. The synthesized nanocapsules with the encapsulated UC dye system consisting of an emitter and a sensitizer show very efficient UC emission in aqueous dispersion under extremely low excitation intensity down to 0.05 W · cm(-2) so that tissue and cells are not affected by the excitation light. The demonstrated sub-linear intensity dependence of the UC emission is of crucial importance for life-science applications as the UC photon could serve as a local or in situ optical excitation source for subsequent light-triggered processes.
authors.affiliation: Max Planck Institute for Polymer Research, Mainz, Germany.
authors.forename: Christian
authors.initials: C
authors.lastname: Wohnhaas
authors.forename: Andrey
authors.initials: A
authors.lastname: Turshatov
authors.forename: Volker
authors.initials: V
authors.lastname: Mailänder
authors.forename: Steffen
authors.initials: S
authors.lastname: Lorenz
authors.forename: Stanislav
authors.initials: S
authors.lastname: Baluschev
authors.forename: Tzenka
authors.initials: T
authors.lastname: Miteva
authors.forename: Katharina
authors.initials: K
authors.lastname: Landfester
mesh_terms: D003609:Dactinomycin / Q000031:analogs & derivatives / Q000378:metabolism; D004339:Drug Compounding / Q000379:methods; D004655:Emulsions / Q000737:chemistry / Q000378:metabolism*; D004735:Energy Transfer; D005260:Female; D005434:Flow Cytometry; D005456:Fluorescent Dyes / Q000378:metabolism; D006367:HeLa Cells; D006801:Humans; D008027:Light; D008422:Materials Testing; D018613:Microscopy, Confocal; D057054:Molecular Imaging / Q000379:methods*; D053769:Nanocapsules / Q000737:chemistry*; D055668:Photochemical Processes / Q000528:radiation effects*; D017785:Photons; D011108:Polymers / Q000737:chemistry* / Q000378:metabolism; D011789:Quantum Theory; D014867:Water
chemical_list: D004655:Emulsions; D005456:Fluorescent Dyes; D053769:Nanocapsules; D011108:Polymers; D014867:Water; D003609:Dactinomycin; C025942:7-aminoactinomycin D